The invention relates to a method for conveying objects, which objects are supplied from at least one supply unit, via a transfer unit, to a switch unit by means of which the objects are carried to a first discharge unit in a first position of the switch unit and to a second discharge unit in a second position of the switch unit.
Such a method as well as a device for carrying out such a method can be derived from the publication WO 98/09894.
The switch unit of said known device is made up of a conveyor belt which can be pivoted up and down about a horizontal pivot pin. A certain amount of time is needed for pivoting the switch unit from one position to the other, during which time no objects can be delivered to a discharge unit. There are mechanical limits to the speed at which the adjustment of said switch unit can take place. For an effective operation of this known device it is necessary, therefore, to maintain a certain spacing between the successive objects, which imposes limits on the number of objects that can be handled per unit time by means of this known device.
According to the invention, detection means are provided for detecting the size of the objects being supplied by means of the supply unit and for detecting the identity of the objects being supplied in connection with the desired convey of the objects either to the first discharge unit and/or to the second discharge unit, and control means are provided for controlling the transport of the objects by means of the supply unit and/or the transfer unit, which control means are influenced by the detection means, all this in such a manner that the spacing between objects lying one behind another on the transfer unit and being delivered to the switch unit in succession that are to be carried to the same discharge unit is smaller than the spacing between objects lying one behind another on the transfer unit and being delivered to the switch unit in succession that are to be carried to different discharge units.
Use is thereby made of the fact that if two successive objects are to be carried to one and the same discharge unit, no time is required for reversing the switch unit, so that these objects to be carried to the same discharge unit can be placed closer together, which means a significant increase of the number of objects that can be moved per unit time.
An efficient device far conveying objects, comprising at least one supply unit which joins a transfer unit, one end of which is disposed near a switch unit that is adjustable between a first position for carrying an object to a first discharge unit and a second position for carrying an object to a second discharge unit, which device is in particular suitable for carrying out the method according to the invention, is obtained in that detection means are disposed near said supply unit, by means of which the size of the objects and the identity of the objects being supplied can be established in connection with the desired convey of the objects either to the first discharge unit or to the second discharge unit, whilst the supply unit includes control means that can be influenced via the detection means, which control means make it possible to influence the velocity at which an object is carried in the direction of the transfer unit by the supply unit.
The invention will now be explained in more detail by means of possible embodiments of a device according to the invention which are schematically illustrated in the accompanying figures.
FIG. 1 schematically shows a few supply units that connect to a transfer unit.
FIG. 2 schematically shows the construction of a switch unit.
FIG. 3 schematically shows another possible embodiment of three supply units connected to a transfer unit.